共查询到20条相似文献,搜索用时 31 毫秒
1.
Hans Mulder Harry Schachter Jerry R. Thomas Koen M. Halkes Johannis P. Kamerling Johannes F. G. Vliegenthart 《Glycoconjugate journal》1996,13(1):107-113
Connective tissue of the freshwater pulmonateLymnaea stagnalis was shown to contain fucosyltransferase activity capable of transferring fucose from GDP-Fuc in 1–2 linkage to terminal Gal of type 3 (Gal1–3GalNAc) acceptors, and in 1–3 linkage to GlcNAc of type 2 (Gal1–4GlcNAc) acceptors. The 1–2 fucosyltransferase was active with Gal1–3GalNAc1-OCH2CH=CH2 (K
m=12 mM,V
max=1.3 mU ml–1) and Gal1–3GalNAc (K
m=20 mM,V
max=2.1 mU ml–1), whereas the 1–3 fucosyltransferase was active with Gal1–4GlcNAc (K
m=23 mM,V
max=1.1 mU ml–1). The products formed from Gal1–3GalNAc1-OCH2CH=CH2 and Gal1–4GlcNAc were purified by high performance liquid chromatography, and identified by 500 MHz1H-NMR spectroscopy and methylation analysis to be Fuc1–2Gal1–3GalNAc1-OCH2CH=CH2 and Gal1–4(Fuc1–3)GlcNAc, respectively. Competition experiments suggest that the two fucosyltransferase activities are due to two distinct enzymes.Abbreviations 2Fuc-T
1–2 fucosyltransferase
- 3Fuc-T
1–3 fucosyltransferase
- MeO-3Man
3-O-methyl-D-mannose
- MeO-3Gal
3-O-methyl-D-galactose 相似文献
2.
Kurt G. I. Nilsson 《Biotechnology letters》1996,18(7):791-794
A new approach for the highly specific preparation of L-serine conjugates of lactosamine and Gal1-3GalNAc is described. Thus, the L-serine derivative of lactosamine Gal1-4GlcNAc-O-(N-Z)-Ser-OEt, was obtained from lactose, employing GlcNAc-O-(N-Z)-Ser-OEt as acceptor and a yeast -galactosidase as catalyst Galp 1-3GalNAc-O-(N-Alloc)-Ser-OMe was obtained from lactose, employing GalNAc-O-(N-Alloc)-Ser-OMe as acceptor and -galactosidase from bovine testes as catalyst. 相似文献
3.
Galili U 《Biochimie》2001,83(7):557-563
Many patients with failing organs (e.g., heart, liver or kidneys), do not receive the needed organ because of an insufficient number of organ donors. Pig xenografts have been considered as an alternative source of organs for transplantation. The major obstacle currently known to prevent pig to human xenotransplantation is the interaction between the human natural anti-Gal antibody and the alpha-gal epitope (Gal alpha 1-3Gal beta 1-4GlcNAc-R), abundantly expressed on pig cells. This short review describes the characteristics of anti-Gal and of the alpha-gal epitope, their role in inducing xenograft rejection and some experimental approaches for preventing this rejection. 相似文献
4.
William Kuhns Volker Rutz Hans Paulsen Khushi L. Matta Michael A. Baker Marijke Barner Maria Granovsky Inka Brockhausen 《Glycoconjugate journal》1993,10(5):381-394
To elucidate control mechanisms ofO-glycan biosynthesis in leukemia and to develop biosynthetic inhibitors we have characterized core 2 UDP-GlcNAc:Gal1-3GalNAc-R(GlcNAc to GalNAc) 6-N-acetylglucosaminyl-transferase (EC 2.4.1.102; core 2 6-GlcNAc-T) and CMP-sialic acid: Gal1-3GalNAc-R 3-sialyltransferase (EC 2.4.99.4; 3-SA-T), two enzymes that are significantly increased in patients with chronic myelogenous leukemia (CML) and acute myeloid leukemia (AML). We observed distinct tissue-specific kinetic differences for the core 2 6-GlcNAc-T activity; core 2 6-GlcNAc-T from mucin secreting tissue (named core 2 6-GlcNAc-T M) is accompanied by activities that synthesize core 4 [GlcNAc1-6(GlcNAc1-3)GalNAc-R] and blood group I [GlcNAc1-6(GlcNAc1-3)Gal-R] branches; core 2 6-GlcNAc-T in leukemic cells (named core 2 -GlcNAc-T L) is not accompanied by these two activities and has a more restricted specificity. Core 2 6-GlcNAc-T M and L both have an absolute requirement for the 4- and 6-hydroxyls ofN-acetylgalactosamine and the 6-hydroxyl of galactose of the Gal1-3GalNAc-benzyl substrate but the recognition of other substituents of the sugar rings varies, depending on the tissue. 3-sialytransferase from human placenta and from AML cells also showed distinct specificity differences, although the enzymes from both tissues have an absolute requirement for the 3-hydroxyl of the galactose residue of Gal1-3GalNAc-Bn. Gal1-3(6-deoxy)GalNAc-Bn and 3-deoxy-Gal1-3GalNAc-Bn competitively inhibited core 2 6-GlcNAc-T and 3-sialyltransferase activities, respectively.Abbreviations AFGP
antifreeze glycoprotein
- AML
acute myeloid leukemia
- Bn
benzyl
- CML
chronic myelogenous leukemia
- Fuc
l-fucose
- Gal, G
d-galactose
- GalNAc, GA
N-acetyl-d-galactosamine
- GlcNAc, Gn
N-acetyl-d-glucosamine
- HC
human colonic homogenate
- HO
hen oviduct microsomes
- HPLC
high performance liquid chromatography
- mco
8-methoxycarbonyl-octy
- Me
methyl
- MES
2-(N-morpholino)ethanesulfonate
- MK
mouse kidney homogenate
- onp
o-nitrophenyl
- PG
pig gastric mucosal microsomes
- pnp
p-nitrophenyl
- RC
rat colonic mucosal microsomes
- SA
sialic acid
- T
transferase
Enzymes: UDP-GlcNAc:Gal1-3GalNAc-R (GlcNAc to GalNAc) 6-N-acetylglucosaminyltransferase,O-glycan core 2 6-GlcNAc-transferase, EC 2.4.1.102; CMP-sialic acid: Gal1-3GalNAc-R 3-sialyltransferase,O-glycan 3-sialic acid-transferase, EC 2.4.99.4. 相似文献
5.
Cornelis H. Hokke Astrid Zervosen Lothar Elling David H. Joziasse Dirk H. van den Eijnden 《Glycoconjugate journal》1996,13(4):687-692
The trisaccharide Gal13Gal14GlcNAc1O-(CH2)8COOCH3 was enzymatically synthesized, within situ UDP-Gal regeneration. By combination in one pot of only four enzymes, namely, sucrose synthase, UDP-Glc 4-epimerase, UDP-Gal:GlcNAc 4-galactosyltransferase and UDP-Gal:Gal14GlcNAc 3-galactosyltransferase, Gal13Gal14GlcNAc1O-(CH2)8COOCH3 was formed in a 2.2 µmol ml–1 yield starting from the acceptor GlcNAc1O-(CH2)8COOCH3. This is an efficient and convenient method for the synthesis of the Gal13Gal14GlcNAc epitope which plays an important role in various biological and immunological processes. 相似文献
6.
Jean-Michel Wieruszeski Jean-Claude Michalski Jean Montreuil Gérard Strecker 《Glycoconjugate journal》1990,7(1):13-26
The major pentasaccharides Fuc(1-2)[GalNAc(1-3)]Gal(1-4)[Fuc(1-3)]Glc and Fuc(1-2) [Gal(1-3)]Gal(1-4)[Fuc(1-3)]Glc, which are normally present in the urine of bloodgroup A Leb and B Leb healthy subjects, were each found to be contaminated by a minor component when analysed by1H-NMR. The determination of these structures, Fuc(1-2) [GalNAc(1-3)]Gal(1-3)[Fuc(1-4)]Glc and Fuc(1-2) [Gal(1-3)]Gal(1-3)[Fuc(1-4)]Glc, was based on the results of methylation analysis and1H/13C-NMR spectroscopy.Abbreviations HPLC
high performance liquid chromatography
- GLC
gas liquid chromatography
- NMR
nuclear magnetic resonance
- COSY
correlation spectroscopy
- Gal
d-galactopyranose
- GalNAc
2-acetamido-2-deoxy-d-galactopyranose
- Glc
d-glucopyranose
- Fuc
l-fucopyranose
- LNDFH I
lacto-N-difucohexaose I (Leb determinant 相似文献
7.
Ossi Renkonen Ritva Niemelä Anne Leppänen Hannu Maaheimo Antti Seppo Leena Penttilä Anja Vilkman 《Glycoconjugate journal》1991,8(4):368-375
Radiolabelled GlcNAc beta 1-3(GlcNAc beta 1-6)Gal (1), GlcNAc beta 1-3)GlcNAc beta 1-6)Gal beta 1-OCH3 (4), GlcNAc beta 1-3(GlcNAc beta 1-6)Gal beta 1-4Glc (7), and GlcNAc beta 1-3(GlcNAc beta 1-6)Gal beta 1-4GlcNAc (10) were cleaved partially with jack bean beta-N-acetylhexosaminidase (EC 3.2.1.30), and the digests were analysed chromatographically. All four oligosaccharides were hydrolysed faster at the (1-6) branch, than at the (1-3) branch, but a high branch specificity was observed only with the glycan 4. The saccharides 1 and 7 resembled each other in the kinetics of the enzyme-catalysed release of their two non-reducing N-acetylglucosamine units, but the glycan 10 was rather different. The partial digestions made it possible to obtain radiolabelled GlcNAc beta 1-6Gal, GlcNAc beta 1-6Gal beta 1-OCH3, GlcNAc beta 1-6Gal beta 1-4Glc, and, in particular, GlcNAc beta 1-6Gal beta 1-4GlcNAc. 相似文献
8.
Lars Hedbys Elisabet Johansson Klaus Mosbach Per-Olof Larsson Alf Gunnarsson Sigfrid Svensson Hans Lönn 《Glycoconjugate journal》1989,6(2):161-168
Gal1-3GlcNAc (1) and Gal1-3GlcNAc-SEt (2) were synthesized on a 100 mg scale by the transgalactosylation reaction of bovine testes -galactosidase with lactose as donor andN-acetylglucosamine and GlcNAc-SEt as acceptors. In both cases the product mixtures contained unwanted isomers and were treated with -galactosidase fromEscherichia coli which has a different specificity, under conditions favouring hydrolysis, yielding besides the desired products, monosaccharides and traces of trisaccharides. The products were purified to >95% by gel filtration, with a final yield of 12% of 1 and 17% of 2, based on added acceptor. In a separate experiment Gal1-6GlcNAc-SEt (3) was synthesized by the transglycosylation reaction using -galactosidase fromEscherichia coli. No other isomers were detected. Compound 3 was purified by HPLC. 相似文献
9.
Itzhak Wirguin Ljubica Suturkova-Milosević Chiara Briani Norman Latov 《Cancer immunology, immunotherapy : CII》1995,40(5):307-310
Keyhole limpet hemocyanin (KLH) is widely used as a carrier molecule to enhance immune responses to administered antigens, and for immunotherapy of bladder and renal carcinoma. In the present study we show, using lectin and antibody binding studies, that native KLH contains Gal(1–3)GalNAc-bearing oligosaccharides, and that immunization with KLH in Lewis rats induces the production of anti-Gal(1–3)GalNAc antibodies. This might explain the beneficial effect of KLH in bladder cancers that express crossreactive Gal(1–3)GalNAc determinants or the T antigen.Supported by NIH grant NS11766 and by the William Rosenwald Family Fund Inc. 相似文献
10.
Sreedhara Sangadala Subramanian Sivakami Joseph Mendicino 《Molecular and cellular biochemistry》1991,101(2):125-143
Summary Two specific -N-acetylglucosaminyltransferases involved in the branching and elongation of mucin oligosaccharide chains, namely, a 1,6 N-acetylglucosaminylsaminyltransferase that transfers N-acetylglucosamine from UDP-N-acetylglucosamine to Gal3GalNAc-Mucin to yield Gal3(GlcNAc6)GalNAc-Mucin and a 3-N-acetylglucosaminyl transferase that transfers N-acetylglucosamine from UDP-N-acetylglucosamine to Gal3(GlcNAC6)GalNAc-mucin to yield GlcNAc3Gal3 (GlcNAc6)GalNAc-Mucin were purified from the microsomal fraction of swine trachea epithelium. The 1,6-N-acetylglucosaminyltransferase was purified about 21,800-fold by procedures which included affinity chromatography on DEAE columns containing bound asialo Cowper's gland mucin glycoprotein with Gal1,3GalNAc side chains. The apparent molecular weight estimated by gel filtration was found to be about 60 Kd. The purified enzyme showed a high specificity for Gal1,3GalNAc chains and the most active substrates were mucin glycoproteins containing these chains. The apparent Km of the 6-glucosaminyltrans-ferase for Cowper's gland mucin glycoprotein containing Gal1,3GalNAc chains was 0.53 µM; for UDP-N-acetylglucosamine, 12 µM; and for Gal 1,3GalNAc NO2ø, 4 mM. The activity of the 6-glucosaminyltransferase was dependent on the extent of glycosylation of the Gal3GalNAc chains in Cowper's gland mucin glycoprotein.The best substrate for the partially purified 3-Glucosaminyltransferase was Cowper's gland mucin glycoprotein containing Gal1,3(GlcNAc6)GalNAc side chains. This enzyme showed little or no activity with intact sialylated Cowper's gland mucin glycoprotein or derivatives of this glycoprotein containing GalNAc or Gal1,3GalNAc side chains.The radioactive oligosaccharides formed by these enzymes in large scale reaction mixtures were released from the mucin glycoproteins by treatment with alkaline borohydride, isolated by gel filtration on Bio-Gel P-6 and characterized by methylation analysis and sequential digestion with exoglycosidases. The oligosaccharide products formed by the 6- and 3-glucosaminyltransferases were shown to be Gal3(GlcNAC6) GalNAc and GlcNAc3 Gal3(GlcNAC6)GalNAc respectively.Taken collectively, these results demonstrate that swine trachea epithelium contains two specific N-acetylglucosaminyltransferases which catalyze the initial branching and elongation reactions involved in the synthesis of O-linked oligosaccharide chains in respiratory mucin glycoproteins. The first enzyme a 6-glucosaminyltransferase converts Gal3GalNAc chains in mucin glycoproteins to Gal3(GlcNAc6)GalNAc chains. This product is the substrate for a second 3-glucosaminyltransferase which converts the Gal3(GlcNAc6)GalNAc chains to GlcNAc3Gal(GlcNAc6)GalNAc chains in the glycoprotein. The 3-glucosaminyltransferase did not utilize Gal3GalNAc chains as a substrate and this results in an ordered sequence of addition of N-acetylglucosamine residues to growing oligosaccharide chains in tracheal mucin glycoproteins.Abbreviations NeuNAc
N-acetylneuraminic acid
- GalNAcol
N-acetylgalactosaminitol
- CGMG
Cowper's gland mucin glycoprotein
- GalNAc-CGMG
Cowper's gland mucin glycoprotein containing GalNAc side chains O-glycosidically linked to serine or threonine
- Gal3GalNAc-CGMC
Cowper's gland mucin glycoprotein containing Gal3GalNAc side chains
- MES
2-(N-morpholino) Ethane Sulfonic acid
- PBS
Phosphate Buffered Saline 相似文献
11.
Wu WC Lai CC Liu JH Singh T Li LM Peumans WJ Van Damme EJ Wu AM 《Neurochemical research》2006,31(5):619-628
Carbohydrate structures between retinal neurons and retinal pigment epithelium (RPE) play an important role in maintaining the integrity of retinal adhesion to underlying RPE, and in retinal detachment pathogenesis. Since relevant knowledge is still in the primary stage, glycotopes on the adult retina of mongrel canines (dog), micropigs and Sprague-Dawley rats were examined by lectino-histochemistry, using a panel of 16 different lectins. Paraffin sections of eyes were stained with biotinylated lectins, and visualized by streptavidin-peroxidase and diaminobenzidine staining. Mapping the affinity profiles, it is concluded that: (i) all sections of the retina reacted well with Morniga M, suggesting that N-linked glycans are present in all layers of the retina; (ii) no detectable human blood group ABH active glycotopes were found among retinal layers; (iii) outer and inner segments contained glycoconjugates rich in ligands reacting with T
α (Galβ1–3GalNAcα1-Ser/Thr) and Tn (GalNAcα1-Ser/Thr) specific lectins; (iv) cone cells of retina specifically bound peanut agglutinin (PNA), which recognizes T
α residues and could be used as a specific marker for these photoreceptors; (v) the retinas of rat, dog and pig, had a similar binding profile but with different intensity; (vi) each retinal layer had its own binding characteristic. This information may provide useful background knowledge for normal retinal physiology and miscellaneous retinal diseases, including retinal detachment (RD) and age-related macular degeneration (ARMD). 相似文献
12.
M. Takagaki R. N. Knibbs J. Roth I. J. Goldstein 《Histochemistry and cell biology》1993,100(2):139-147
Monoclonal antibodies were prepared against the trisaccharide Gal1-3Gal1-4GlcNAc, a sequence which occurs on the surface of Ehrlich ascites tumor cells as well as in thyroglobulin, laminin and a variety of other proteins. This was accomplished by immunizing BALB/c mice with the fraction of Ehrlich cell membrane glycoproteins obtained by affinity chromatography on aGriffonia simplicifolia I (GS I) column which selectively binds -d-galactosyl-terminated structures. Detection of Gal1-3Gal1-4GlcNAc-specific antibodies was accomplished by employing glycoproteins containing the trisaccharide sequence; fusion with spleen cells from an immunized mouse was accomplished in the presence of polyethylene glycol (PEG1500). An enzyme-linked immunosorbent assay (ELISA) system was used to identify two clones (2.10G and 6.8E), which recognized the desired trisaccharide conjugate. These clones also recognized a thyroglobulin fraction isolated by GS I affinity chromatography and murine laminin, both of which possess the Gal1-3Gal1-4GlcNAc sequence. Inhibition of antibody-trisaccharide reactivity, examined employing an ELISA assay, revealed that two trisaccharides, Gal1-3Gal1-4GlcNAc/Glc, were the best inhibitory haptens; Gal1-4GlcNAc (LacNAc), Gal1-3Gal and Gal1-4Glc (lactose) were poor inhibitors. Indirect immunofluorescence staining of unfixed Ehrlich cells using the monoclonal antibody at 4° C revealed fluorescence over the entire cell surface. Indirect immunogold labeling of semithin and ultrathin sections of aldehyde fixed and Lowicryl K4M-embedded Ehrlich cells resulted in specific labeling of the cell surface and internal structure. Immunoblot analysis revealed that removal of the -galactosyl residues of laminin by -galactosidase abolished reactivity with the monoclonal antibodies. The availability of this antibody, which belongs to the IgM family of immunoglobulins, now makes possible the detection of this sugar sequence on cells and tissue sections, as well as on glycoproteins in solution. 相似文献
13.
14.
Ossi Renkonen Leena Penttilä Anne Makkonen Ritva Niemelä Anne Leppänen Jari Helin Anja Vainio 《Glycoconjugate journal》1989,6(1):129-140
A novel linear tetrasaccharide, Gal1-4GlcNAc1-6Gal1-4GlcNAc, was isolated from partial acid hydrolysates of metabolically labeled poly-N-acetyllactosaminoglycans of murine teratocarcinoma cells. It was characterized by exo-glycosidase sequencing and by mild acid hydrolysis followed by identification of all partial cleavage products. The tetrasaccharide, and likewise labelled GlcNAc1-6Gal1-4GlcNAc, resisted the action of endo--galactosidase (EC 3.2.1.103) fromE. freundii at a concentration of 125 mU/ml, while the isomeric, radioactive teratocarcinoma saccharides Gal1-4GlcNAc1-3Gal1-4GlcNAc and GlcNAc1-3Gal1-4GlcNAc were cleaved in the expected manner.Abbreviations WGA
wheat germ agglutinin
- BSA
bovine serum albumin
- [3H]GlcNAc1-4-GlcNAc1-4GlcNAcOL
N,N,NN'-triacetylchitotriose reduced with NaB3H4 相似文献
15.
Evelyn Jabri David R. Quigley Marjorie Alders Maria Hrmova Cathy S. Taft Patricia Phelps Dr. Claude P. Selitrennikoff 《Current microbiology》1989,19(3):153-161
(1–3)--d-Glucan synthase activity ofNeurospora crassa was localized to the plasma membrane by autoradiography of colloidal gold-labeled plasma membranes. The active site of glucan synthase for substrate hydrolysis was determined to be cytoplasmic facing. However, glucan synthase activity present in intact protoplasts was partially sensitive to Novozym 234 and to glutaraldehyde treatments, suggestive that enzyme activity is transmembrane. Enzyme activity also directed the formation of microfibrils in vitro. Taken together, these and previous results support the following scheme for glucan synthesis: 1. The sequential addition of glucose residues from UDP-glucose to glucan chains occurs on the cytoplasmically facing portion of glucan synthase. 2. As each glucan chain is synthesized, it is extruded to the extracytoplasmic side of the plasma membrane. 3. As each chain is extruded, it forms interchain hydrogen bonds with adjacent chains, resulting in glucan microfibril assembly. 相似文献
16.
Rare polyagglutinable NOR erythrocytes contain unusual globoside extention products terminating with a Galα1-4GalNAcβ1-3Gal-
unit. This trisaccharide epitope is recognized by recently characterized antibodies naturally occurring in most human sera
(Duk et al., Glycobiology, 15, 109, 2005). These antibodies represent two major types of fine specificity. All these antibodies are most strongly inhibited by Galα1-4GalNAcβ1-3Gal
(NOR-tri), and weakly by Galα1-4Gal. However, the type 1 antibodies are strongly inhibited by Galα1-4Galβ1-3Gal-R and weakly
by Galα1-4GalNAc, while the type 2 antibodies show the opposite reactivities with these two oligosaccharides. Similar antibodies
have now been found in horse, rabbit and pig sera. The antibodies were purified from animal sera by affinity chromatography
on Galα1-4GalNAcβ1-3Gal-human serum albumin(HSA)-Sepharose 4B conjugate. The specificity of the antibodies was determined
by binding to ELISA plates coated with several α-galactosylated oligosaccharide-polyacrylamide (PAA) or -HSA conjugates and
by inhibition with synthetic oligosaccharides. The purified antibodies bound specifically to conjugates containing NOR-tri.
The inhibition of binding showed that the animal sera also contain two types of anti-NOR antibodies: type 2 was found in the
horse serum, and a mixture of both types was present in rabbit and pig serum. These results indicate that anti-NOR, a new
and distinct kind of anti-αGal antibody, are present in animal sera and show similar specificties and diversity as their counterparts
found in human sera. 相似文献
17.
Our recent studies have revealed the existence of two distinct Gal: 3-O-sulfotransferases capable of acting on the C-3 position of galactose in a Core 2 branched structure, e.g., Gal14GlcNAc16(Gal13)GalNac1OBenzyl as acceptor to give 3-O-sulfoGal14GlcNAc13(Gal13)GalNAc1OB 20 and Gal14GlcNAc16(3-O-sulfoGal13)GalNAc1OB 23. We herein report the synthesis of these two compounds and also that of other modified analogs that are highly specific acceptors for the two sulfotransferases. Appropriately protected 1-thio-glycosides 7, 8, and 10 were employed as glycosyl donors for the synthesis of our target compounds. 相似文献
18.
Takeuchi T Nishiyama K Yamada A Tamura M Takahashi H Natsugari H Aikawa J Kojima-Aikawa K Arata Y Kasai K 《Carbohydrate research》2011,(13):1837-1841
Galβ1-4Fuc is a key structural motif in Caenorhabditis elegans glycans and is responsible for interaction with C. elegans galectins. In animals of the clade Protostomia, this unit seems to have important roles in glycan–protein interactions and corresponds to the Galβ1-4GlcNAc unit in vertebrates. Therefore, we prepared an affinity adsorbent having immobilized Galβ1-4Fuc in order to capture carbohydrate-binding proteins of C. elegans, which interact with this disaccharide unit. Adsorbed C. elegans proteins were eluted with ethylenediaminetetraacetic acid (EDTA) and followed by lactose (Galβ1-4Glc), digested with trypsin, and were then subjected to proteomic analysis using LC–MS/MS. Three annexins, namely NEX-1, -2, and -3, were assigned in the EDTA-eluted fraction. Whereas, galectins, namely LEC-1, -2, -4, -6, -9, -10, and DC2.3a, were assigned in the lactose-eluted fraction. The affinity of annexins for Galβ1-4Fuc was further confirmed by adsorption of recombinant NEX-1, -2, and -3 proteins to the Galβ1-4Fuc column in the presence of Ca2+. Furthermore, frontal affinity chromatography analysis using an immobilized NEX-1 column showed that NEX-1 has an affinity for Galβ1-4Fuc, but no affinity toward Galβ1-3Fuc and Galβ1-4GlcNAc. We would hypothesize that the recognition of the Galβ1-4Fuc disaccharide unit is involved in some biological processes in C. elegans and other species of the Protostomia clade. 相似文献
19.
Yu. A. Knirel H.-J. Gabius O. Blixt E. M. Rapoport N. R. Khasbiullina N. V. Shilova N. V. Bovin 《Glycoconjugate journal》2014,31(1):7-12
Galectins are multifunctional effectors, for example acting as regulators of cell growth via protein-glycan interactions. The observation of capacity to kill bacteria for two tandem-repeat-type galectins, which target histo-blood epitopes toward this end (Stowell et al. Nat. Med. 16:295–301, 2010), prompted us to establish an array with bacterial polysaccharides. We addressed the question whether sugar determinants other than β-galactosides may be docking sites, using human galectins-4, -8, and -9. Positive controls with histo-blood group ABH-epitopes and the E. coli 086 polysaccharide ascertained the suitability of the set-up. Significant signal generation, depending on type of galectin and polysacchride, was obtained. Presence of cognate β-galactoside-related epitopes within a polysaccharide chain or its branch will not automatically establish binding properties, and structural constellations lacking galactosides, like rhamnan, were found to be active. These data establish the array as valuable screening tool, giving direction to further functional and structural studies. 相似文献
20.
Endo--galactosidase (EC 3.2.1.103) ofBacteroides fragilis, at 250 mU ml–1, did not cleave the internal galactosidic linkage of the linear radiolabelled trisaccharide GlcNAc1-6Gal1-4GlcNAc, or those of the tetrasaccharides Gal1-4GlcNAc1-6Gal1-4GlcNAc and Gal1-4GlcNAc1-6Gal1-4Glc. The isomeric glycans which contained the GlcNAc1-3Gal1-4GlcNAc/Glc sequence were readily cleaved.Abbreviations GlcNAc
2-acetamido-2-deoxy-d-glucose
- Lact
lactose
- MT
maltotriose
- MTet
maltotetraose
-
R
MTet
chromatographic migration rate in relation to that of maltotetraose 相似文献